Portable electric refrigerator



R. G. sHElDLER. ErAL 2,678,544

PORTABLE ELECTRIC REFRIGERATOR 5 sheets-sheet 1 M m T May 18, 1,954.

Filed Jim@ 15, 1952 May 18, 1954 R. G. SHEIDLR ETAL PORTABLE; ELEc'rRIc-REFRIGERATOR -5 Slineets-Sheet 2 Filed June 15, 1952 uk Illlllllllllllllll I4 9 Fama/7B. (Var/ y@ A17/wam May 18, 1954 R. G.sHElDLER Em. 2,678,544

l PORTABLE ELECTRIC REFRIGERATOR y Filed June 1:5I 152 l I 5Sheets-Sheet 31 R. G. sHElDLER vE1- AL 2,678,544 PORTABLE ELECTRICREFRIGERATOR May 13, 1954 5 Sheets-Sheet 4 Filed June 15, 1952 May 18,1954 R. G. sHElDLER ETAL 2,678,544

PORTABLE ELECTRIC REFRIGERATOR 5 Sheets-Sheet 5 Filed June 15, 1952 "vtTi;

,lill\llll lllll \l\llll||\\ Illini E Patented May 18, 1954 `PORTABLEELECTRIC REFRIGERATTOR Robert G. Sheidler and Truman B. Clark,Mansfield, Ohio, assignors to The Tappan Stove Company, Mansfield, Ohio,a corporation of Ohio Application June 13, 1952, Serial No. 293,373

9 Claims.

This invention relates to electric refrigerators which are especiallyadapted for military use in transport airplanes when ferrying personnelfrom place to place. Although the refrigerator was particularly designedfor military use it is equally Well adapted for civilian use.

Military transport planes vary greatly in size and capacity and aresometimes used to ferry personnel several thousand miles, and at othertimes to ferry personnel only a relatively short distance. Precookedmeals for the personnel being transported are kept in a refrigeratoraboard the plane during iiight. Before taking off, the refrigerator isstocked with meals in accordance with the number of persons being flownand the distance of the flight. Sometimes food must be carried forboththe outgoing and the return iiight. In transport airplanes theWeight and size of equipment are of prime consideration. Consequently,refrigerators therefor should be of such size as to carry only therequired number of meals for a given flight, and they should beconstructed as lightly as possible to give the required service.

In certain parts of the World when a military transport plane stands inthe sun on the ground for only a short time the ambient temperaturetherein sometimes reaches 166. Therefore refrigerators for militarytransport planes must be so constructed that they will operate equallyWell in both 10W ambient temperature and in extremely high ambienttemperatures. They should also be so constructed that the refrigeratingmechanism therefor can be quickly and easily removed as a unit andreplaced with another unit in the case of damage or failure.

With the foregoing in mind We designed a mobile refrigerator of largecapacity, but which is relatively small in size, which is relativelylight in weight, Which will operate equally Well in both low and`extremely high ambient temperatures, in which the refrigeratingmechanism can be quickly removed and replaced as a single unit, and inwhich the capacity and size can be varied as desired. p

Our new and improved design of refrigerator comprises generally a basesection, a top section, one or more intermediate sections and anelectric refrigerating mechanism of conventional type. The base section,which is mounted upon a pair of spaced parallel rails Whichextend outbeyond one side thereof, comprises a bottom wall,

a rear Wall, a pair of spaced side Walls connected to the bottom andrear Walls and a door which deiine` a storage compartment open at theupper end thereof. The intermediate sections each comprise a rear Wall,a pair of spaced side Walls connected to the rear wall, and a door whichdefines a storage compartment open at the top and bottom and having thesame horizontal dimensions as the compartment in the base section. Thetop may be removably clamped to the upper end of the base section toclose the compartment therein, or an intermediate section may beremovably clamped to the upper end of the base section and then the topremovably clamped to the upper end of the intermediate section. Thebottom of the top section has a shallow upwardly extending recesstherein which is adapted to register with the upper end of the storagecompartment in the base section or an intermediate section. If more thanone intermediate section is used they are removably clamped together andto the base section, and the top is then removably clamped to the upperend of the uppermost intermediate section. When intermediate sectionsare used the compartments therein align with each other and with thecompartment inthe base section to provide a single compartment ofgreater height and consequently greater storage capacity. By adding orsubtracting intermediate sections the storage capacity of therefrigerator may be varied as desired to suit the requirements of aparticular flight.

The base section has a closed chamber Within the storage compartmentwhich extends from the front to the rear of the compartment along oneside wall and the bottom wall. Access is had to the chamber through arectangular opening in the adjacent side wall. There is an air intakeduct into the chamber through the lower end of the inner transverse Wallof the chamber, and there is an air discharge duct which extendsupwardly from the chamber along the adjacent side Wall of the basesection and terminates iiush with the upper end of the side wall. Eachintermediate section has a duct extending from the bottom to the topthereof along one side Wall Which are adapted to register With eachother and with the duct in the base section.

The refrigerating mechanism is of conventional type and comprises theusual evaporator, compressor, condenser, storage tank and electric motorall of Which are mounted upon a suitable platform which is adapted toseat upon the rails which extend out irom under the base section. Therefrigerating mechanism also includes a motor driven fan which ismounted in front of the evaporator in position to draw air through andaround the evaporator. When in operative position the evaporator and fanare disposed within the chamber in the base section, being insertablethereinto through the opening in the side wall of the base section. Theplatform also carries a plug door which closes the opening into thechamber. Suitable clamping means are provided to removably clamp theplatform and the mechanism and door thereon in position. When it isdesired to change the refrigerating mechanism the clamps are releasedand the platform and the mechanism carriedV thereby are moved. outwardlyas a single unit upon the rails until the evaporator is withdrawn from`the chamber after which the unit may be carried away and a new unitinstalled.

Food is stored in the storage compartment 4 refrigerator as shown inFig; 1 from the front to the rear thereof, the planes of the sectionsbeing indicated by the lines 5 5 and G respectively on Fig. 4;

Fig. 7 is a view similar to Fig. 1 showing an intermediate sectionapplied to the base section in which the refrigerator of our inventionis upon a plurality of sheet metal trays which are slidably mounted uponsuitable tracks which are secured to the side walls and extend from thefront to the rear of the compartment. The peripheries of the trays arespaced from the walls of the compartment to provide unobstructed pathsfor the downward passage of air along the walls. VThe trays also have aplurality of slots therein through which air may flow. The slots in onetray are arranged to vertically align with the slots in the other traysto provide additional paths for the down ow of air.

In operation the fan draws air downwardly from the top of thecompartment along the various paths and into the evaporator chamberthrough the air inlet port at the bottom of the chamber. The air is thendrawn through the evaporator, where it is cooled, and forced up throughthe discharge duct into the shallow recess in the top section whichdiffuses the air over the top of ,the compartment. A continuous cir.-culation and cooling of the air Within the storage compartment is thusmaintained.

The principal object of the invention is to provide a mobilerefrigerator having a large storage capacity, but which is relativelylight in weight and small in size as compared to the capacity thereof.

Another object of the invention is to provide a refrigerator of thistype which is so constructed that the capacity thereof can be Vquicklyand easily varied in accordance with particular requirements.

Another object of the invention is to provide a refrigerator of thistype which will operate eiciently in either low or extremely highambient temperatures.

Another object of the invention is to provide a refrigerator of theaforesaid type in which the. refrigerating mechanism can be quickly andeasily removed and replaced as a single unit.

Other and more limited objects of the invention will be apparent fromthe following specification and the accompanying drawings forming a partthereof in which:

Fig. 1 is a front elevation of a refrigerator, constructed according toour invention, showing the base section and the top section only beingused to provide the minimum storage capacity;

Fig. 2 is a horizontal section taken on the line 2 2 of Figs. 1 and 4;

Fig. 3 is a horizontal section taken on the line 3 3 of Figs. 1 and 4; Y

Fig. 4 is a vertical section through the refrigerator as shown in Fig. 1from side to side thereof, the plane of the section being indicated bythe line 4 4 of Figs. 2 and 3;

Figs. 5 and 6 are vertical sections through the shown as adjustedY forits minimum capacity, by reference characters, the numeral I indicates abase section, 2 a top section, and the numeral 3 indicates generally therefrigerating mechanism. The base section I comprises a bottom wall 4, arear wall 5, and the side walls 6 and i which are all joined together toprovide a storage compartment 8 which is open at the top and frontthereof. The front of the compartment 8 is closed by a door 9 which issecured to the side wall S by hinges I0. The door 9 is held in closedposition by a suitable latch I I which is arranged to be released by ahandle I2 which is disposed in a recess I3 in the front of the door. Thewalls 4, 5, 6 and 1 and the door 9 are all made up of spaced inner andouter sheet metal casing I4 and I5 with the space therebetween packedwith suitable insulating material Iii. The forward edges of the wallsli, 6 and 'l and the upper edges of the walls 5,'6 and 'I are all facedwith thin Vstrips I'I of plastic material such as Bakelite A sealinggasket I8 of heat-insulating material is secured to the inner face ofthe door 9 in position to tightly seal the front of the compartment 8.lThe top of the compartment 8 isclosedby the top section 2 which isremovably secured in place by clamps I9 and dowel pins I9a carried bythe side walls 5 and 1. The top section 2is made up of the spaced upperand lower sheetY metal walls 2@ and 2i which are connected together bythe sheet metal peripheral wall 22. The space between the walls ispacked with insulating material 23, and the front of the top section2^is faced with a thin strip 24 of plastic similar to the strips il. anupwardly extending rectangular recess 26 formed ther-ein which isadapted to register with the upper end of the storage compartment 8. Asealing gasket 25 of suitable heat insulating material is permanentlysecured to the upper edges of the walls 5, 6 and I Vover the facingstrips il thereon.

A vertical sheet metal partition 3e extends upwardly from the bcttomwalld and inwardly from the side wall I at the forward edges thereof. Theinner edge of the partition 3d is connected to the rear wall 5 by atransverse vertical sheet metal partition 3I, and the'upper edges of thepartitions 30 and 3l are connected to the rear walls 5 and the side wall'l by a horizontal sheet metal partition 32.V The partitions SEB. SI and32 and the walls 5 and 'I dene a chamber 33 within the storagecompartment 8. Access is had to the chamber 33 through an enlargedrectangu lar opening 29 through the side wall '1. A horizontal sheetmetal partition 34 which extends between the partition 3l and the walls5 and 3 slightly above the bottom wall 4 provides an air TheV bottom ofthe top section 2 hasY intake duct 35into the chamber 33.` Elongatedslots 36 are provided in the partition 34 for the entrance of air intothe `duct35. Some air can also enter the chamber 33 through an elongatedslot 28 in the .horizontal partition 32. A vertical `sheet metalpartition 3l which extends upwardly from the chamber 33 te the upper endof the base section I in slightly spaced relation to the side wall .'Iprovides an air discharge duct 38 from the chamber 33.

Food is stored in the compartment 8 upon a plurality of similarrectangular trays 46 which are slidably mounted upon tracks il which aresecured to the wall 6 and the partitions 3i and 3l and extend from thefront to the rear of the compartment 8. The tracks 4I are spaced fromthe wall 6 and the partitions 3i and 31 except at the ends 42 and 43thereof which are offset to engage the wall or partitions and be securedthereto. The spacing of the tracls 4l from their supporting wall` orpartition provides uninterrupted paths along the wall 5 and partitions3| and 31 for the downward flow of air. The inner edges of the trays 4Bare spaced from the rear wall 5 by a pair of spaced parallel verticalribs Lili, to provide a path along the rear wall 5 for the downward flowof air. When the trays 46 are in position with the inner edges thereofin contact with the ribs 44, the forward edges of the trays terminateinwardly of the door 9 so that a path for the downward flow of air isalso provided along the door 9. Latching means (not shown) are providedfor locking the trays in position. The trays 4D have a plurality ofspaced parallel elongated slots i5 therein which are so arranged thatthe slots in any tray are in vertical alignment with the slots in theother trays. Additional paths are thus provided for the downward flow ofair. The slots 36 in the partition 3d, and the slots 4.5 in the trays d.are rimmed by upturned flanges 46. The base section I is mounted upon apair of spaced parallel rails il which extend out from under thebasesection I beyond the lside l thereof.

The refrigcrating mechanism generally inclicatefi by the numeral 3 is aconventional` electric refrigerating mechanism which comprises the usualevaporator, compressor,` condenser, refri erant storage tank and motorwhich are mounted upon a platform 55 which is adaptedto seat on andsiide along the railsll'. All of the refrigeratlng mechanism` with theexception of the evaporator are enclosed by a removable cover 5i havingventing louvers 52 therein. The evaporator 53 is disposed within thechamber 33, being inserted thereinto through the opening 29 in the sidewall i. The opening 29 is closed by a plug door 54 which is also carriedby the platform 5d. The refrigerating mechanism also includes amctordriven fan 55 which is disposed between the evaporator 53 and theplug door 54 within the chamber 63. The platform 56 and therefrigerating mechanism and the plug door 54 are locked in position by apair of releasable latches 5t.

.ln operation the fan 55 draws air downwardly along the various pathsdescribed and into the evaporator or cooling chamber 33 through theintake duct 35. The air is then drawn through and around the evaporator53, which cools it, and forced up through the discharge duct 38 into therecess 26 in the top section 2 which diffuses the cooled air over thetcp of the compartment 6. In this way a continuous circulation andcooling of the air within the refrigerator is 6.. maintained.Conventional means (not shown) is provided for regulating the operationof the refrigerating mechanism in order to maintain the desiredtemperature within the storage compartment 8.

If the refrigerating mechanism 3 should become damaged or out of orderit can be removed as a single unit by releasing the latches 56 andsliding the platform 56 back along the rails il until the evaporator hasbeen removed from the compartment 33. The unit can then be taken awayfor repairs and a new unit placed upon the rails fil and slid intoposition.

When it is desired to enlarge the storage compartment 8 the tcp section2 is removed from the base section l and one or more intermediatesections are clamped to the top of the base section and then the topsection 2 is clamped to the top oi' the uppermost intermediate section.Each intermediate section comprises a rear wall and two side walls whichconstitute extensions of the rear wall 5 and the side walls 6 and of thebase section I. Each intermediate section also has its own door.

Reference will now be had to Figs. 7 to lo cf the drawings which showone intermediate section 66 interposed between the base section i andthe top section 2. The section 66 comprises the rear wall 6i, the sidewalls 62 and. 63 and a door 64 which is secured to the forward end ofthe side wall 62 by hinges 65 and is held in closed position by latchingmeans 46 which is actuated by a handle 6T disposed in a recess 68 in thefront of the door 64. The construction of the walls 6I, 62 and 63 andthe door 64 is similar to the construction of the walls and door of thebase section I in that they comprise inner and outer sheet metal casings68 and I6 with the space therebetween packed with insulating material7|. The upper edges of the walls si, 62 and 63 and the forward edges ofthe walls 52 and` 63 are faced with plastic strips t2, similar to thestrips I1 on the base section i. The doors 64 carries a sealing gasket73 similar to the gasket I8 on the door 9, and a sealing gasket I4similar to the gasket 25 is permanently secured to the upper ends of thewalls 6i, 61 and 63 over the facing strips 12. The forward ends of thewalls 62 and 63 are connected together at the lower ends thereof by asheet metal tie bar 15 which is also faced with a plastic strip l2. Theintermediate section 66 is removably secured to the upper end of thebase section. i by the clamps I9 and the dowel pins lila carried by thebase section. The top section 2 is removably secured to the intermediatesection 66 in position to close the upper end thereof by clamps 'iti anddowel pins 'H carried by the intermediate section 65. A vertical sheetmetal partition 56 which extends from the bottom to the top of theintermediate section 66 in closely spaced relation to the side wall 63dennes an air discharge duct 6I which registers with and constitutes anextension of the air discharge duct 36 in the base section I. Trays 156are slidably sup ported in the intermediate section upon tracks 62 whichare identical in construction and instalu lation with the tracks 4I inthe base section i. The intermediate section 60 thus constitutes anupward extension of the base section. i and storage compartment 8therein, and increases the capacity of the storage compartment S by thecapacity of the intermediate section. lf still further capactiy isrequired, additional intere 7c mediate sections may be interposedbetween the base section I and the top section 2.

From the foregoing it will be apparent to those skilled in this art thatwe have provided a very simple and eicient mechanism for accomplishingthe objects of the invention.

It is to be understood that we are not limited to the specificconstruction shown and described herein as various modifications may bemade therein within the scope of the appended claims.

What is claimed is:

l. A refrigerator comprising a bottom section having a bottom wall, arear wall, two side walls and a door defining a storage compartment openat the upper end thereof, a top section remov ably secured to the upperend of said bottom section in position to close the upper end of saidstorage compartment, partitions in said storage compartment defining achamber at a lower corner of said storage compartment, an air inlet fromsaid compartment into said chamber, an air outlet from said chamber intosaid storage compartment, a refrigerating mechanism including anevaporator and a fan, said evaporator and fan being disposed within saidchamber and said fan being operative to induce a flow of air from saidcompartment into said chamber through said inlet and past saidevaporator and out through said outlet back into said compartment, apluraliti7 of trays disposed in said storage compartment, and means bywhich said trays are removably supported in vertically spaced relationin said storage compartment with the peripheral edges thereof spacedfrom the bounding walls of said compartment to provide uninterruptedpaths for the downward flow of air along the inner faces of saidbounding walls.

2. A refrigerator as dened in claim l in which each of said trays has aplurality of elongated slots therein, the slots in one tray beingdisposed in vertical alignment with the slots in the other trays toprovide additional paths for the downward iiow of air.

3.V A refrigerator comprising a bottom section having a bottom wall, arear wall, two side walls and a door, an intermediate section having arear wall, two side walls and a door, said intermediate section beingremovably secured to the upper end of said bottom section with the rearand side walls thereof in vertical alignment with the rear and sidewalls of said bottom section, the said walls and doors of said bottomsection and said intermediate section defining a storage compartmentopen at the upper end thereof, a top section removably secured to theupper end of said intermediate section in position to close the upperend of said compartment, partitions in said storage compartment dening achamber at a lower corner of said storage compartment, an air inlet fromsaid compartment into said chamber, an air outlet from said chamber intosaid storage compartment, a refrigerating mechanism including anevaporator and a fan, said evaporator and fan being disposed within saidchamber and said fan being operative to induce a flow of air from saidcompartment into said chamber through said inlet and past saidevaporator and out through said outlet back into said compartment, aplurality of trays disposed in said storage compartment, and means bywhich said tra s are removably supported in vertically spaced relationin said storage compartment with the peripheral edges thereof spacedfrom the bound ing walls of said compartment to provide unin- Y alongthe inner faces of said bounding Walls.

4. A refrigerator as defined in claim 3 in which each of said trays hasa plurality of elongated slots therein, the slots in one tray beingdisposed in vertical alignment with the slots in the other trays toprovide additional paths for the downward flow of air.

5. A refrigerator comprising a bottom section having a bottom wall, arear wall, two side walls and a door defining a storage compartment openat the upper end thereof, a top section removably secured to the upperend of said bottom section in position to close the upper end of saidstorage compartment, a Vertical partition extending upwardly from saidbottom wall and forwardly from said rear wall and a horizontal partitionextending forwardly from said rear wall between the upperrend of saidvertical wall and one of said side walls, said partitions defining achamber within said storage compartment, a second horizontal partitionextending between said vertical Vpartition and the other of said sidewalls in slightly spaced relation to said bottom wall and defining anair inlet duct from the bottom 0f said storage compartment into saidchamber, a sec-V ond vertical partition extending upwardly from saidhorizontal partition in slightly spaced relation to the said one of saidside walls and dening an air discharge duct from said chamber into theupper end of said storage compartment, a refrigerating mechanismincluding an evaporator yand a fan, said evaporator and said fan beingdisposed within said chamber and said fan being operative to induce aflow of air from the lower end of said storage compartment through saidinlet duct into said chamber and past said evaporator and out from saidchamber through said discharge duct into the upper end of said storagecompartment, a plurality of trays disposed in said storage compartment,and means by which said trays are removably supported in verticallyspaced relation in said storage compartment with the peripheral edgesthereof spaced from the bounding walls of said compartment to provideuninterrupted paths for the downward dow of air along the inner faces ofsaid bounding walls.

6. A refrigerator as defined in claim 5 in which each of said trays hasa plurality of elongated slots therein, the slots in one tray beingdisposed in vertical alignment with the slots in the other trays toprovide additional paths for the downward flow of air.

7. A refrigerator comprising a bottom section having a bottom Wall, arear wall, two spaced side walls and a door defining a storagecompartment open at the upper end thereof, a vertical partitionextending upwardly from said bottom wall and forwardly from said rearwall and a horizontal partition extending forwardly from said rear wallbetween the upper end of said vertical wall and one of said side walls,said par- Y titions deiining a chamber within said storage compartment,a second horizontal partition extending between said vertical partitionand the other of said side walls in slightly spaced relation to saidbottom wall and defining an air inlet duct from the bottom of saidstorage compartment into said chamber, a second vertical partitionextending upwardly from said horizontal partition in slightly spacedrelation to the said one of said side walls and dening an air dischargeduct from said chamber into the upper end of said storage compartment,an intermediate 9 section having a rear wall, two spaced side walls, adoor and a vertical partition which is slightly spaced from one of saidintermediate side walls and defines an air discharge duct in saidintermediate section, said intermediate section being removably securedto the upper end of said bottom section with the rear and side wallsthereof in vertical alignment with the rear and side walls of saidbottom section and the discharge duct therein in register with thedischarge duct in said bottom section, a top section removably securedto said intermediate section in position to close the upper end thereof,a refrigerating mechanism including an evaporator and a fan, saidevaporator and said fan being disposed within said chamber and said fanbeing operative to induce a flow of air from the lower end of saidstorage compartment through said inlet duct into said chamber and pastsaid evaporator and out from said chamber through said discharge ductinto the upper end of said storage compartment, said refrigeratingmechanism being mounted upon a platform which is removably secured toone of the walls of said bottom section,

8. A refrigerator comprising a bottom section having a bottom wall, arear wall, two spaced side walls and a door defining a storagecompartment open at the upper end thereof, a vertical partitionextending upwardly from said bottom wall and forwardly from said rearwall and a horizontal partition extending forwardly from said rear wallbetween the upper end of said vertical wall and one of said side walls,said partitions deiining a chamber within said storage compartment, asecond horizontal partition extending between said vertical partitionand the other of said side walls in slightly spaced relation to saidbottom wall and dening an air inlet duct from the bottom of said storagecompartment into said chamber, a second vertical partition extendingupwardly from said horizontal partition in slightly spaced relation tothe said one of said side walls and deiining an air discharge duct fromsaid chamber into the upper end of said storage compartment, anintermediate section having a rear Wall, two spaced side walls, a doorand a vertical partition which is slightly spaced from one of saidintermediate side walls and defines an air discharge duct in saidintermediate section, said intermediate section being removably securedto the upper end of said bottom section with the rear and side wallsthereof in vertical alignment with the rear and side walls of saidbottom section and the discharge duct therein in register with thedischarge duct in said bottom section, a top section removably securedto said intermediate section in position to close the upper end thereof,a refrigerating mechanism including an evaporator and a 1an, saidevaporator and said fan being disposed within said chamber and said fanbeing operative to induce a flow of air from the lower end of saidstorage compartment through said inlet duct into said chamber and pastsaid evaporator and out from said chamber through said discharge ductinto the upper end of said storage compartment, a plurality of traysdisposed in said storage compartment, and means by which said trays areremovably supported in vertically spaced relation in said storagecompartment with the peripheral edges thereof spaced from the boundingwalls of said compartment to provide uninterrupted paths for thedownward iiow of air along the inner faces of said bounding walls.

9. A refrigerator as deiined in claim 8 in which each of said trays hasa plurality of elongated vslots therein, the slots in one tray beingdisposed in vertical alignment with the slots in the other trays toprovide additional paths for the downward W of air.

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